Cable trough

ABSTRACT

A precast concrete trough having a first member with bottom cross braces, sides and removable top and a second member having a single cross brace and sides fitting exterior of the first member.

United States Patent 11 1 1111 3,858,614 Moore et al. 1 1 Jan. 7, 1975[54] CABLE TROUGH 2,862,367 12/1958 Silverstein ct a1. 61/11 1 1 WilliamGabe" Moore; Frank 1 331231332 51133? F3317???51:11:11: .31.???1133Hendricks, Jr., both of R0. Box 3573, 5000 Castlewood Rd., FOREIGNPATENTS OR APPLICATIONS VKiQ A QQQQLAYQ .5 Mn 61,476 4/1968 Germany138/105 23,953 8/1901 Switzerland... 138/105 [22] filed. Nov- 19721,221,181 1/1960 France 138/155 [21] Appl. No.: 306,870

- Related U.S. Application Data Primary Examiner-Herbert Goldstein [63]Continuation-impart of Ser. No. 158,706, July 1, Attorney, Agent, -MBernard, Brown 1971. Roberts & Sutherland [52] U.S. Cl. 138/105, 174/3751 1111.01. F161 1/00,1-:02 1 29/10 1571 ABSTRACT Fieid of Search138/103 105, 108, A precast concrete trough having a first member with138/175; 61/11; 174/37 38, 48 bottom cross braces, sides and removabletop and a second member having a single cross brace and sides [56]References Cited fitting exterior of the first member.

UNITED STATES PATENTS Mahoney et a1. 138/175 2 Claims, 6 Drawing Figures'II-ATENTEDJAN 71975 3.858.614

SHEET 3 OF 3 CABLE TROUGH CROSS-REFERENCE TO RELATED APPLICATIONS Thisapplication is a continuation-in-part, and claims the priority of ourprior patent application entitled Cable Trough tiled July 1, 1971, Ser.No. 158,706.

BACKGROUND OF THE INVENTION Control cable and metal conduit in electricpower substations must be enclosed and protected to prevent abrasionwith a consequent breaking of insulation and power failure. Priormethods of protecting the cable include direct burial or burial of thecable encased in plastic conduit, aluminum cable trays, and poured inplace concrete cable troughs.

There has heretofore been invented a precast concrete structure, whichwhen assembled, forms the basis for an underground trench. It isillustrated in US. Letters Pat. No. 3,862,367, entitled Precast CableTrench. It includes a bracket having upstanding posts, supporting ledgesoutside the posts and a central base. Separate side wall panels rest onthe ledges and are biased against the posts by the dirt fill when thedevice is in stalled in a trench.

SUMMARY OF THE INVENTION This invention is a precast concrete troughthat has a unitary base adapted for completely above groundinstallation. The unitary base member has cross braces on which theconduit may rest and side members which support and protect the conduitand serve as a mounting for the protective top.

The principal advantage of this invention is the ease of installationand consequent cost reduction in building the substation, andultimately, the cost of electric power to the consumer. After majorconstruction of the substation, this concrete trough may be rapidly putin place, directly on the ground, and the cables laid thereon withlittle or no prior preparation of the ground and no subsequentreplacement of the fill.

This is in contrast to the prior cable casing devices which require theconstruction of a trench before installation of the cable protectivedevice and the cable itself, and then require the replacement of thedirt into the trench and the removal of the excess fill.

The invention will be further described with reference to the attacheddrawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view ofthe cable trough including the slip joint, end closures, and universalangle joint section.

FIG. 2 is a perspective drawing of an underground installation partiallycut away.

FIG. 3 is a cross-section of the cable trough taken on lines 3-3 of FIG.2.

FIG. 4 is a perspective of an above-ground installation showing theuniversal joint abutting a control station.

FIG. 5 is a perspective view of the cable trough as assembled prior tofilling in an underground installation.

FIG. 6 is a cross-section taken on the lines 6-6 of FIG. 5.

DESCRIPTION OF PREFERRED EMBODIMENTS The major components of thisinvention are the cable trough 10, the slip-joint 11, the trough cover12, the end closure 13, and the universal angle joint 19.

Each individual cable trough 10, is an integral precast reinforcedconcrete body. It has side walls 20 and 21, which are connected at theouter edges of the lower inside wall, by trough bottom braces, 22 and23. Each brace has reinforcing bevel 24 at either end. The brace isgenerally rectangular with rounded edges at the top to prevent abradingthe cables.

The side wall has hand holds 25, on the outer surfaces, and has aninternal taper in the vertical plane 26, and a bevel 27.

The tapered feature of the side wall allows the cable trough 10 to becast in the inverted position and removed easily from the mold while theend bevels 27 allow a more secure interfitting of the pieces in theassembled form. The top cover as shown is half the length of eachindividual cable trough, and is a unitary structure having a body 30 andrecesses 31, to allow a secure fit on the top of the side walls. Boththe cable trough 10, the trough cover 12, and the other portions willhave conventional reinforcing bars 28.

The end closure 13 has a terminating wall 34 of a height equal to theheight of side walls 20 and 21 of the cable trough. The end closure alsohas side braces 35 and 36, at the end of the terminating wall, andspaced apart so that they may slide with their inner surface slightlyoutside the outer surfaces of side walls 20 and 21 of the last cabletrough.

The slip-joint 11 is attached to the center of sliding walls 38 and 39.These sliding walls are spaced apart a distance, like the side braces ofthe end closure, to allow them to slide with their inner surfacesslightly outside the outer surface of the side walls of the cabletrough.

The universal angle joint 19 has, as parts, four posts 14, four drivepins 15, one or more blanks 16, a frame 17, and a series of universaljoint covers 18.

The four posts are spaced so that their inner surfaces fit outside outersurfaces of the connecting cable troughs 10. The drive pins arepartially inserted in the ground and the posts are mounted on the pinsthrough post bores 40.

The frame 17 is a unitary structure having four angle iron spanning bars42, joined at their ends and having downwardly facing frame pins 43which cooperate with the upper end of the post bore 40 to further alignthe universal angle joint and to serve as a mount for the universalcover 18, which has a cover body 46 and end recesses 47 to allow asecure fit between the cover and the frame.

The inner sides of the posts 40 have vertical post grooves 41 whichallow blank 15 having the blank body 44 and blank tongue 45 to interfitwhen the universal angle joint is used as an L or T joint rather than acrossjoint.

OPERATION OF THE INVENTION The operation of this invention will bedescribed primarily with respect to its construction and installationsince the structure operates only in repose to protect the cable.

The installation will of course depend on where the cables are to bestrung and which types of cables are involved. Shown in FIG. 4 is acable running from the ladder entrance of control house 55, through theuni- 3 versal angle joint to a cable getaway into an underground metalconduit 53.

A particular feature of this invention is that this cable trough is aswell suited to above-ground installation As below-ground installation.The above-ground installation is illustrated in FIG. 4 while abelow-ground installation is shown in FIG. 2, which requires digging atench 50, followed by installation of the cable trough, and thenbackfilling and carting leftover fill.

Each of the cable trough sections are laid in place in abuttingajoinment, with their beveled ends assuring a more complete seal. I

The position of the universal angle joint would conventionally be laidout initially, the pins driven into the ground and the posts mountedthereon. I

As the line of cable troughs approach the terminating point, theslip-joint may be used to fill in the side wall space between two fixedpoints. I

The end closure is also somewhat laterally adjustable to form atermination for cable troughs leading to an underground conduit getaway.

After the cable troughs are installed, but before the conduit is laid inplace, a fill 51 such as a few inches of pea gravel, is placed in thesection between the cross braces. This fill insures proper drainage andalso holds the above-ground installation in position.

The conventional flexible control cable 52 or the metal conduit 53 maybe placed directly on top of the cross brace 22. An alternative is touse a wall fastener 56 to hold the conduit above the floor of thetrough.

I claim:

1. A precast concrete trough for supporting and enclosing electriccables for above-ground or belowground installation, which comprises aseries of abutted sections in which each section has:

a. a unitary base member including side walls and cross braces,

b. said cross braces of generally rectangular cros section,

c. said cross braces having enlarged reinforced bevels at either end,

d. said cross braces in parallel alignment and abutting the innersurface of said side wallsat the lateral extremities of said side walls,

c. said cross braces further aligned so that their lower surface isaligned with the lower surface of said side walls,

f. said side walls case into the unitary base piece with said crossbraces to form a unitary free standing structure capable of supportingand enclosing the electric cables in an above-ground installation, anaperture formed by the side walls and the cross braces in the bottom ofthe section for entrance and exit of the electric cable,

h. a top member demountably attached to the base member and spanning thedistance between the side walls, said top member generally rectangularand forming a load bearing surface.

. an expansion section having a single elongated, generally rectangular,base section with enlarged bevels at either end and a pair of sidewalls, said cross brace abutting said side walls at the center of theinner surface, the lower surface of the cross brace further aligned withthe lower surfaces of the side walls, the inner surfaces of the sidewalls so spaced apart to slide outside the outer surfaces of the sidewalls of the said abutting sections.

2. The combination of claim 1 further including an angle sectionassembly for interconnecting runs of troughs, said angle sectioncomprising four vertical rectangular posts, each post having a centralbore, anchoring pins adapted for partial sinking in the ground, saidstakes cooperating with said bore, a rectangular spanning frame havingdepending pins, said pins cooperating with the bore at the top of saidposts, said spanning frame of a length to space said vertical postsapart so that the inner surfaces of the posts fit outside the outersurface of the vertical wall of said abutting sections, said verticalposts having on their inner walls vertical grooves, a blanking wallfitting in said vertical grooves and blanking the space between saidposts and top sections resting on said spanning frame.

1. A precast concrete trough for supporting and enclosing electriccables for above-ground or below-ground installation, which comprises aseries of abutted sections in which each section has: a. a unitary basemember including side walls and cross braces, b. said cross braces ofgenerally rectangular cross section, c. said cross braces havingenlarged reinforced bevels at either end, d. said cross braces inparallel alignment and abutting the inner surface of said side walls atthe lateral extremities of said side walls, e. said cross braces furtheraligned so that their lower surface is aligned with the lower surface ofsaid side walls, f. said side walls case into the unitary base piecewith said cross braces to form a unitary free standing structure capableof supporting and enclosing the electric cables in an above-groundinstallation, g. an aperture formed by the side walls and the crossbraces in the bottom of the section for entrance and exit of theelectric cable, h. a top member demountably attached to the base memberand spanning the distance between the side walls, said top membergenerally rectangular and forming a load bearing surface. i. anexpansion section having a single elongated, generally rectangular, basesection with enlarged bevels at either end and a pair of side walls,said cross brace abutting said side walls at the center of the innersurface, the lower surface of the cross brace further aligned with thelower surfaces of the side walls, the inner surfaces of the side wallsso spaced apart to slide outside the outer surfaces of the side walls ofthe said abutting sections.
 2. The combination of claim 1 furtherincluding an angle section assembly for interconnecting runs of troughs,said angle section comprising four vertical rectangular posts, each posthaving a central bore, anchoring pins adapted for partial sinking in theground, said stakes cooperating with said bore, a rectangular spanningframe having depending pins, said pins cooperating with the bore at thetop of said posts, said spanning frame of a length to space saidvertical posts apart so that the inner surfaces of the posts fit outsidethe outer surface of the vertical wall of said abutting sections, saidvertical posts having on their inner walls vertical grooves, a blankingwall fitting in said vertical grooves and blanking the space betweensaid posts and top sections resting on said spanning frame.